Submitted to: Journal of Animal Science
Publication Type: Review Article
Publication Acceptance Date: April 3, 2001
Publication Date: N/A
Technical Abstract: Feed intake is the cornerstone of animal productivity. The consequences of inadequate intake include inhibited growth, delayed puberty, infertility, reduced milk production, and lowered resistance to parasites and disease. Factors that influence intake include age, metabolic demand (gestation, lactation, level of physical activity), thermal environment, photoperiod, disease, and psychosocial stress. Conditions also exist where intake is adequate for health and well-being, but is limiting for optimum performance and productivity. The role of the central nervous system (CNS), particularly the hypothalamus, has long been recognized in the control of appetite. A variety of bioactive peptides and protein neurohormones are involved in the modulation of neural pathways that stimulate or suppress appetite. Complementary DNA (cDNA) sequences and clones for these regulatory factors in livestock are rapidly being generated, providing new tools for physiological studies and the production of recombinant/syntheti hormones and analogs. An understanding of the interactions between environmental factors and the mechanisms of appetite control is fundamental to the development of practical approaches to optimize feed intake, which will lead in a new era of research in redefining the limits of productivity. An important component of this future research will be to ensure that enhanced intake is utilized efficiently for the production of high quality food products.